The present invention relates to zinc-bromine secondary batteries of the general class described in the following U.S. patents.
Bloch U.S. Pat. No. 2,566,114 PA1 Zito U.S. Pat. No. 3,285,781 PA1 Zito U.S. Pat. No. 3,640,777 PA1 Bloch U.S. Pat. No. 3,373,058 PA1 Blue U.S. Pat. No. 3,408,232 PA1 Bloch U.S. Pat. No. 3,576,503 PA1 deRossi U.S. Pat. No. 3,625,764 PA1 deRossi U.S. Pat. No. 3,738,870 PA1 Maricle U.S. Pat. No. 3,806,368 PA1 deRossi U.S. Pat. No. 3,811,945 PA1 Walsh U.S. Pat. No. 3,816,177 PA1 Zito U.S. Pat. No. 3,827,915 PA1 Leddy U.S. Pat. No. 3,929,506
Despite technical promise and substantial effort this energy storage system has not achieved commercial acceptance. Problems inhibiting system use include self discharge characteristics; hazards associated with bromine; high internal resistance (and consequent power loss); severe material requirements and costs associated with the artifacts necessary to accommodate the above factors; polarization; thermal runaway; gas evolution; and, perhaps of over-riding significance, system degradation in extended usage such that long-term reliability could not be assured for the batteries.
It is the object of the present invention to provide effective energy storage overcoming the foregoing problems, particularly the avoidance of long term system degradation.